Debossing creates a depression in stock (such as sheets or paper) and the equivalent process in embossing creates an upstanding portion which is therefore in relief. Debossing is therefore a mirror image of embossing. With an embossing die, which is a female die, there is an equivalent male die termed a counter. The planar stock is passed between the two dies which are then subjected to pressure and thereby creates the raised image.
One type of female die used in these processes is a photopolymer die. Typically the photopolymers used have a high Shore hardness. The photopolymers are processed by means of photoresist. The non image area is washed away with water by soft nylon brushes. The photopolymer is adhered to a thin metal backing plate which is preferably steel. The photopolymer die is secured to a platen base by means of adhesive tape and recently by means of magnetic attraction between the backing plate and magnets positioned in the platen or cylinder bed.
Counters can be made in accordance with at least three known prior art methods. The first is that the counters are cut by hand from paper using the PRAGOPLAST (Registered Trade Mark) system which involves feathered paper with an adhesive backing. The second is the use of moulded counters which are fabricated from fiberglass, putty, and various other plastics which are moulded under both heat and/or pressure to form the male counter. The third type of counter is fabricated from photopolymer and has a film backing which is also of polymeric or other plastic material. The film backing normally is transparent or translucent and thus aids in the alignment of the two dies since the operator can visualize the intended mating.
It is necessary to align or position the counter on the platen of the stamping machine, or cylinder in the case of a rotary machine. For the first type of counters, the counter is hand cut in position after being secured to the platen or cylinder. For both moulded counters and film backed photopolymer counters, the counter is positioned by means of a “reverse” fit. That is to say, the male counter is positioned by hand over the female die until the male protrusions of the counter appear to mate with the recesses of the female die. Once a snug fit has been achieved, double sided adhesive tape is placed on the back of the counter (that is the surface of the counter away from the female die). Then the platen or cylinder is brought into contact with the adhesive tape in order to fasten the counter (or male die) to the platen or cylinder.
However, there is a danger that the counter can move out of its correct position or alignment in the process of fastening the counter to the platen or cylinder. There is also a risk that the male counter can be damaged in the securing process.
Die cutting involves the use of a die to cut and/or crease stock (such as paper sheets or thin sheets of plastic) so as to fabricate a blank for an article such as an envelope, a folder, or the like. The die normally has a base of inexpensive material such as timber, five ply, particle board, or the like. Mounted on the base, edge upper most, are thin strips of steel. In the case of a desired cut, the upper edge is sharp and constitutes a knife. In the case of a desired crease, the upper edge of the strip is rounded. Extending along either side of at least the knife strips is a strip of resilient material which in its uncompressed state has a surface higher than the upper edge of the knife. The two strips of resilient material function as an ejector mechanism to prevent the cut stock becoming jammed on the knife.
In general cutting stock to shape using die cutting is a separate function to that of embossing or debossing of the stock. Thus if a job calls for cutting, and embossing or debossing 1000 items, in general this requires 2×1000 or 2000 operations as the item must be separately embossed or debossed, and then die cut.
However, in recent times it has been known to combine both cutting and either embossing or debossing. This has been possible using an expensive magnesium (or other metal) die to carry out the embossing/debossing. Such metal dies require environmentally burdensome acids to etch away the die material or must be hand engraved or CNC machined. The embossing/debossing die is generally held on the cutting die by means of double sided adhesive tape or screwed or bolted into the cutting tool and must be painstakingly aligned with the cutting die and with any counter required.